Todd, The "old" Uniform Building Code Standards (specifically Standard 7-7, Part V) allowed you to calculate the fire-resistance of wood-framed walls based on testing of the individual wall components. Nominal 2x4 studs at 16" on center have a "Time Assigned" of 20 minutes. Combined with some mineral insulation (and maybe some sheet metal), I think you've got a pretty good (and partially documented) argument for at least a 15 minute "thermal barrier."
Andrew Cook, Plans Analyst Santa Rosa (CA) Fire Department -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Todd Williams - FPDC Sent: Friday, April 11, 2008 1:32 PM To: [email protected] Subject: RE: thermal barrier The GC figures he can pack a lot of mineral wool for the price of 90+ sprinklers At 04:06 PM 4/11/2008, you wrote: >Todd, Without sounding smug, wouldn't it be easier to install the sprinkler ? > >John Drucker >Fire Protection Subcode Official (AHJ) > > >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] > On Behalf Of Todd Williams - FPDC >Sent: Friday, April 11, 2008 3:40 PM >To: [email protected] >Subject: RE: thermal barrier > >Do thermal barrier and fire resistance mean the >same thing? You could put sheet metal on metal >studs and it would be a non-combustible >construction would have a certain resistance, >but would not be a thermal barrier. The >definition in NFPA 13R give a certain definition >to thermal barrier and the handbook commentary >gives notes basically what several people have >said. However, my situation is a little more complicated (are you surprised?) > >What I am working on is a 90-unit wood frame >hotel with a 13R system. The original design had >a modular bathroom, which has been scrapped in >favor of a stick-built one. The way this is >framed, a layer of sheetrock cannot be installed >behind the front and back of the tub (the side >along the back wall can be). The proposal has >been made to fill the void space behind the >cast-iron tub with mineral wool. My question is >does this provide the required thermal barrier >and how would I go about proving it? > > > >At 09:14 AM 4/11/2008, you wrote: > >Double check that, usually you need "Type X" > >5/8" to achieve the 1 hr. rating. According to the IBC it takes two > >layers, staggered of 1/2" > >each side to get a 1 hour rating. See Item > >14-1.2 in Table 719.1(2). One layer of 5/8" > >Type X on each side will also give 1hr, Item 14-1.3. > > > >You will most likely be within the 15 minute window with standard 1/2" > >sheet rock over studs with no exposed combustibles. Make sure all > >penetrations into the stud cavity are sealed with fire caulk. > > > >Thermal barrier is between the bathroom and the adjacent space. > > > > > >Craig L. Prahl, CET > >Fire Protection Group > >Mechanical Department > >CH2MHILL > >Lockwood Greene > >1500 International Drive > >PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - > >864.599.8439 [EMAIL PROTECTED] http://www.ch2m.com > > > >-----Original Message----- > >From: [EMAIL PROTECTED] > >[mailto:[EMAIL PROTECTED] On Behalf Of Eric > >Tysinger > >Sent: Friday, April 11, 2008 8:47 AM > >To: [email protected] > >Subject: RE: thermal barrier > > > >Don't forget the thermal barrier is required behind the fixtures and > >must extend to the floor even behind the bathtubs. If you need to prove > >the rating (15min) a simple spec sheet on gypsum board should provide > >that. Any UL fire rating details will show ½" gypsum on each side of a > >metal stud wall as at least one-hour. > > > >Eric Tysinger > >Design Manager > >Wayne Automatic Fire Sprinklers, Inc. > > > > > >-----Original Message----- > >From: [EMAIL PROTECTED] > >[mailto:[EMAIL PROTECTED] On Behalf Of Dewayne > >Martinez > >Sent: Friday, April 11, 2008 7:35 AM > >To: [email protected] > >Subject: RE: thermal barrier > > > >I believe a 1/2" sheet of gyp bd meets this criteria but you may want > >to show him 13R (07)6.9.2. > >The requirement for the thermal barrier has been removed. > >Dewayne > > > >-----Original Message----- > >From: [EMAIL PROTECTED] > >[mailto:[EMAIL PROTECTED] > >On Behalf Of Todd Williams - FPDC > >Sent: Friday, April 11, 2008 6:04 AM > >To: [email protected] > >Subject: thermal barrier > > > >NFPA 13R includes an exclusion for sprinklers in bathrooms less than > >55 sqft and where the walls behind fixtures "are of non-combustible or > >limited combustible materials providing a 15-minute thermal barrier". > >Is there any way to quantify if this criteria is met? A thermal barrier > >to what? I have an AHJ questioning this. > > > >Todd G. Williams, PE > >Fire Protection Design/Consulting > >Stonington, Connecticut > >www.fpdc.com > >860.535.2080 > >_______________________________________________ > >Sprinklerforum mailing list > >[email protected] > >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > > >To Unsubscribe, send an email > >to:[EMAIL PROTECTED] > >(Put the word unsubscribe in the subject field) > >_______________________________________________ > >Sprinklerforum mailing list > >[email protected] > >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > > >To Unsubscribe, send an email > >to:[EMAIL PROTECTED] > >(Put the word unsubscribe in the subject field) > >_______________________________________________ > >Sprinklerforum mailing list > >[email protected] > >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > > >To Unsubscribe, send an email > >to:[EMAIL PROTECTED] > >(Put the word unsubscribe in the subject field) > >_______________________________________________ > >Sprinklerforum mailing list > >[email protected] > >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > > > >To Unsubscribe, send an email > >to:[EMAIL PROTECTED] > >(Put the word unsubscribe in the subject field) > >Todd G. Williams, PE >Fire Protection Design/Consulting >Stonington, Connecticut >www.fpdc.com >860.535.2080 >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > >To Unsubscribe, send an email to:[EMAIL PROTECTED] >(Put the word unsubscribe in the subject field) > >CONFIDENTIAL AND PROPRIETARY: >This email message is intended only for the use >of the individual or entity to which it is >addressed and may contain information that is >privileged and confidential, nor is it, unless >specifically stated, intended to be relied upon >by any person or persons other than the >individual or entity named above and no >warranties or representations are made or >intended to persons or entities not named >above. If the reader is not the intended >recipient, you are hereby notified that any >dissemination, distribution or copying of this >communication is strictly prohibited. If you >have received this communication in error, >please notify us immediately by telephone, >return this message to the address above and delete all copies. Thank you. > >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > >To Unsubscribe, send an email to:[EMAIL PROTECTED] >(Put the word unsubscribe in the subject field) Todd G. Williams, PE Fire Protection Design/Consulting Stonington, Connecticut www.fpdc.com 860.535.2080 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
